Such a roller typically has a roller core and a roller sleeve fastened to the periphery of the roller core that is composed of several segments distributed over the periphery with mutually facing side faces, the segments having clamping shoulders on their end faces with first clamping faces and the segments being detachably fastened on the end faces by at least one respective fastening ring to the roller core that engages over the clamping shoulders of the segments. Such a roller is preferably a press roller for a roller press for hot-briquetting or hot-compacting, for example hot-briquetting or hot-compacting of directly reduced iron (DRI). Relative to the invention, granular material also refers to dusty or powdery material. The (bilateral) side faces are surfaces that delimit the respective segment angularly. A side face of a segment consequently confronts a side face of a segment that is adjacent or follows angularly. The side faces are aligned so as to extend axially, and they are secured in place axially and radially of the roller axis and delimited by the inner periphery and the outer periphery of the respective segment.
A roller press generally has two press rollers rotating in opposite directions. During briquetting or compacting, the granular bulk material is compacted between the rollers. For this purpose, the roller sleeve, which is composed of the segments, is equipped with pressing tools that can have mold cavities for the briquetting or compacting. However, the invention also includes press rollers with segments that are provided with another wear-protection layer, for example for the size-reduction of material. Particularly during hot-briquetting or hot-compacting, the press rollers are exposed to high temperatures from the material to be processed, so that the segments themselves also reach high temperatures. This applies, for example, to the processing of reduced iron ores or sponge iron, in which the temperatures can reach up to 900° C. At high temperatures, the segments and their pressing tools are generally subject to wear. In order to limit the wear, such press rollers and their casings are generally cooled, for example by water. It has long since been known to integrate cooling channels into the clamping rings of the rollers.
Since the (tool) segments are generally subject to wear, they are detachably and thus exchangeably fastened to the roller core. The fastening is done with by bilateral fastening rings that are also referred to as locking rings or clamping rings and that engage over the bilateral clamping shoulders of the segments. High demands are placed on the stability of these segments in practice, since they are subjected to high loads.
A roller press for the hot-compacting and hot-briquetting of bulk materials with press rollers with segments is known, for example, from DE 25 36 670 (U.S. Pat. No. 4,123,971). The segments are provided with lugs or shoulders on which fasteners engage that secure the segments to the roller core. In this previously known design, clamping brackets supported on the roller core are provided as fasteners that are pressed against the segment by a tension bolt. Alternatively, cooled shrink rings, radially arranged screws or the like are also proposed as fasteners.
The fastening of the segments by fastening rings or clamping rings that engage over the clamping shoulders of the segments is also known in practice. The clamping shoulders generally have the same cross section over the entire peripheral region of the segment. The clamping bolts are provided at the region of the side faces between two mutually adjacent segments. For this purpose, suitable grooves are worked into the side faces to receive the clamping bolts. The known designs have proven themselves in principle, but they can be further developed with respect to their stability and durability. This is where the invention comes in.